Ship&#39;s propeller of the fluid-operated reaction type



Sept. 15, 1925.

H. WIEDEMANN SHIPS PROPELLER OF THE FLUID OPERATED REACTION TYPE Filed Dec. 26, 1924 Patented Sept. 15, 1925.

U NITE D S T A-TE'S ATE NT OFF ICE HANS WIEDEMANN, OF BERLIN, GERMANY.

- SHIPS- PROPELLER'OF THE FLUID-OPERATED 'BiEAGTION TYPE. I

Application filed- Decembe1fl26, .1924. Serial No; 758,275.

T 0 all whom it may concern Be it known that I, HANS lVInonMANN, a citizen of the Commonwealth of Germany and resident of Berlin, Germany, have invented certain new and useful Improve. ments in Ships Propellers of the Fluid-Operated Reaction Type, for which I have. applied for the following patents, in Germany, 28 May, 1.9;3 (W 63915XI/65 f).

This invention relates to ships propellers and has for its object to provide an improved propeller of the kind in whichfluid under pressure is forced through one or more nozzles or openings at the stern of the ship.

Propeller arrangements of the abovemenhollow body rotatably supported after the- .manner of the boss of a screw propeller is provided with spirally arranged exit slots and is fed with water under pressure.

The operation is explained somewhat as follows: lVith the usual jet-propellers the particles of water issuing from the slotsalways strike one another-in the previously expelled jet and thereby produce an only slightly operative jet which is somewhat thin and is shot at high velocity towards the rear; in the present case onthe other hand, the particles of water strike repeatedly upon stationary water particles and thereby experience a powerful stemming or heaping-up action which produces very high water pressures the power action of which can .be completely utilized as apropeller. Experiments have shown that the thrust of such a propeller, which is very small in air (namely, only equal to the powercorresponding to the speed of the same amount of water), is increased several times upon immersing the propeller in water, which apparently is due to. the stemming action obtained in water, and produces as a final result a slowly escaping jet having a cross section many times as great as the cross section of the propeller, with a corresponding efliciency.

lVith this propeller, if the paths of the jets are directed oppositely to the direction of travel, proper to the angle of inclination of the water ets, the reaction causes a rotation-which apparently ISBS- .sential for the production of the stemming effect and the reaction thrust upon the propeller body; by controlling this rotary movement various degrees of thrust and .speedof travel can be obtained, as may be desired. For instance, by holding the propeller stationary, against itstendency to rotate, by means of a brake for example, the

forward components producednby the rotation of the spiralslots are neutralized, so that a greater absolute rearward component of the velocity of the jet is produced which is available for a greater speed of travel. of

.the ship. The adaptabilityof-the propeller in fact extends further; for instance, the propeller can be driven in the opposite direction to its above mentioned inherent tendency to rotate, asinuthe case of a. screw propeller the blades of which are replaced by the spiral. slots. .In thiscase ca further increase isobtainedofthe rearwardly directly speed component, corresponding to a further increaseof speed of travel of-;the ship.

The rotarydrive canbe provided by me chani calnieans asin the case of the usual propellers; it can also be producedby-water turbines .withguiding and vrotaryblading, or by reaction nozzles-whichmaymbe provided on .the propellerso asvto setiit in rotation by. means of the propelling pressure-water, in which. case the, -'LlSLltll :Shlft duct can also be dispensed with.

A constructional example of the invention is illustrated in the. accompanying drawings, in which Fig. 1 is a longitudinal section of ,one form of the improved,propellenwith spiral slots, havingcsloping. and rearwardly 5directed passages, in .conjunctioirwith.a driving water-turbine;

Fig.2 is a cross. section. through the turbine blading,. looking .towardscthe rear, on the plane indicated by thelline IIII of "Figure 1.

. ply pipe 3 by a centrifugal pump 5 driven by a motor 4, and issuing in fan-like jets in such a manner as to form helical surtaces.

purpose of making use of this in the most advantageous manner the slots should be rearwardly directed as shown. This provides at the same time a further rearward component producing a propulsive effect by immediate reaction. In consequence of this sloping direction, however, a tangential reaction component is produced which sets the propeller in rearward rotation, that is, opposite to that mentioned above.

WVith an arrangement of the kind described above the following conditions are found to be present. In consequence of the slots the outer masses of water enter all parts of the slots in an unused condition, that is not yet forced into jets, whether the pro peller is atrest or rotating forward or backwards; the said water produces in the slots a stemming action giving a powerful propelling effect, and flows oti rearwardly in a strong current of but slight speed. The most favourable action in this case, according to experiments which have taken place hitherto, appears to occur when the propeller is left free to its own inherent rot: tion.

In practically carrying out the invention the propeller body 1 is closed at the rear end by a head 6 secured to the sternpost of the ship in a manner similar to known screw propeller bosses. The body 1 is provided with webs or ribs 7 at one end and with a closing plate 8 at the other end and is supported upon a spindle 9 which runs in bearings in the sternpost; a thrust-bearing (not shown) can, if considered necessary be provided to transmit the propelling power to the ship in a favourable manner. Into the casing of the propeller, which is formed as a labyrinth packing 10, issues the pressure-watersupply pipe 3.

Between the propeller body 1 and the packing ring 10 a rotating set of turbine blades with a set of stationary guide blades 12 fixed on the pipe 8, and with covering ring 18, to form a water turbine (Fig. 2) which enables the propeller to be set in rotation in 11 is arranged, which is combined the direction indicated by the arrow. A valve member 14: slidably supported in the interior of the pipe 3 enables the turbine to be cut out, or brought into operation, ac cording to requirements, and therewith a wide range of regulation from rearward up to forward rotation of the propeller, the slide 14: being moved by means of any suitable operating device traversing the water pipe. I

For rearward travelling either a suitable separate propeller or a second group of exit slots may be provided together with a reversing slide on the forward propeller serving for alternately shutting off and bringing the same into operation.

I claim:

1. A ships propeller of the fluid reaction type comprising in combination a water supply pipe, a hollow rotatable body of a cylinder-like shape and spirally formed water exit slots in the circumference of said body.

2. A ships propeller of the fluid reaction type comprising in combination a water supply pipe, a hollow rotatable body of a cylinder-like shape, spirally formed water exit slots in the circumference of said body, and means for rotating said body in the manner of a usual ships screw.

3. A ships propeller of the fluid reaction type comprising in combination a water supply pipe, a hollow rotatable body of a cylinder-like shape, spirally formed water exit slots in the circumference of said body, and a water turbine connected to said body, so as to rotate it, and connected to said water supply pipe so as to receive driving water.

4:. A ships propeller of the fluid reaction type comprising in combination a water supply pipe, a hollow rota-table body of a cylinder-like shape and spirally formed water exit slots in the circumference of said body, the said water exit slots having inclined passages rearwardly direct-ed.

5. A ships propeller of the fluid reaction type comprising in combination a water supply pipe, a hollow rotatable body of a cylinder-like shape and spirally formed water exit slots in the circumference of said body, the said water exit slots having inclined passages rearwardly directed, and

means provided on said body adapted to alter its rotating velocity or holding 1t stationary.

HANswiEnEiniNit 

